That's how it works mate. Whenever the altcoins are rising. Definitely, bitcoin price is dropping. When bicoin is rising. Altcoin is crashing. Its vice-versa. But its not happen everytime. There are some altcoin can still go up even bitcoin is rising. That's still depend how hyped the coin is. Look at STR.

that is usually what happens, some traders sell their alt coins if they think they will profit in btc to USD trading at the time, same thing on when they think btc price will fall ofcourse they will trade in alt coins resulting price increase

The trends aren't exactly like that and aren't predictable, but alts are definitely traded in relation to Bitcoin - so a drop in alts can mean a flow into Bitcoin, and a drop in Bitcoin can mean a flow into alts, but there could be any number of other reasons which go against these tendencies.

This isn't guaranteed, but often an overall altcoin pump like now will look like this (chronologically):-Rise in alts-Drop in Bitcoin, making some more newbies flow into alts-Rise and alts and Bitcoin together-Eventually, drop in alts and continued rise in Bitcoin

To some extent it is correct but the altcoins which are good worthy are not getting much affected by the bitcoin fluctuations. But most of the altcoins are getting affected due to selling in altcoins and taking bitcoins profit due to price increase.

Also it seems that to purchase or sell altcoins, you need to trade with bitcoin, so the trade is always the equal and opposite... funds flow will follow market sentiment between these differing investments

But I read there is an DDOS attack on two major altcoin exchanges and traders are rushing to secure their investments. Now a days all altcoins are not trading to obey the rule of maintaining their fiat value as all are growing hence I guess no more we can expect the down fall for altcoins when bitcoin finds up surge.

It's not the general trend anymore, because everything has changed since alts are proving to be working. Even if Bitcoin is UP, if the altcoins are preferred against Bitcoins' usage, I see price increase more than getting decreased. Altcoins are now more valuable than Bitcoins if compared in technology, and few have the potential too to soon take over Bitcoins.

I bought some XRP and XLM and they were doing really well, but it seems all the market cap gains flowed out and into BTC.

Don't follow the crowd. When you follow coins that have been statistically doing good chances are you lose money. You picked a bad time to buy into alts especially when BTC was rising so quickly, better luck next time. BTC is correcting again though, so you may have a better time later.

Bitcoin UP = Altcoin DOWN it was.Depends what alts,in facts main altcoins gain much more to dollar than btc.We need to see fiat money market,dollar is weakening to emerging currencys,there is path situation in USA very poor GDP and inflation rise.I think some money from fiat markets is coming to crypto

Bitcoin UP = Altcoin DOWN it was.Depends what alts,in facts main altcoins gain much more to dollar than btc.We need to see fiat money market,dollar is weakening to emerging currencys,there is path situation in USA very poor GDP and inflation rise.I think some money from fiat markets is coming to crypto

Yeah, USD value has got a big decline in value. If the same continues overcoming dollar won't be a big matter. The fall has happened and retaining haven't happened yet and if war takes place surely once again major drop can be experienced. As quoted some countries moving into cryto too might be a reason. Few alts were in the pumping, but due to the bitcoins forward rally it gets hidden.

as far as bitcoin-altcoin price relations go, there has never been a solid rule for them to interact with each other movements.sometimes when bitcoin price goes up with some rally, altcoins follow.sometimes when bitcoin price goes up, altcoins get dumped.sometimes when bitcoin price goes down altcoins start pumpingsometimes when bitcoin price goes down altcoins get dumped also.

this has been the story so far.but i have found one rule to work in most of the times.when an altcoin is being traded against both bitcoin and USD, when bitcoin price goes up, that altcoin (since they are mostly being traded with bitcoin) goes down because they need to keep the USD value stable otherwise arbitrage will balance it out. and when that happens it creates a panic sell wave in altcoin market which causes the altcoin to crash even more.

now this rule is couple with some other stuff, such as altcoins being in a bubble and poloniex were offline so they couldn't prevent the crashes, etc. was causing altcoin to dump hard in the past 2 days.